Trump has called repeatedly on China to help exert pressure on North Korea, particularly with regard to its nuclear ambitions.

The Trump administration is considering banning travel by U.S. citizens to North Korea, officials said Tuesday, as outrage grew over the death Otto Warmbier and President Donald Trump declared it a “total disgrace.”

Secretary of State Rex Tillerson, who has the authority to cut off travel to North Korea with the stroke of the pen, has been weighing such a move since late April, when American teacher Tony Kim was detained in Pyongyang, a senior State Department official said. No ban is imminent, but deliberations gained new urgency after Warmbier’s death, said the official, who requested anonymity to discuss internal diplomatic discussions.